Train braking system



Dec. 22, 1936. E. E. HEW|TT TRAIN BRAKING SYSTEM Filed Sept. 24, 1935 2Sheets-Sheet 1 \N\NWNNNN \mJ MUN Wm, www

INVENTO'R E LLIE E. HEWITT BY Zf/ d/ ATTORNEY Dec. 22, 1936. E. E.HEwlTT TRAN BRAKING SYSTEM Filed Sept. 24, 1935 2 SheetS--Sheel'l 2INVENTO'R E LLIE EHEWlTT BY ATTORNEY WNN m@ Nk wk Patented Dec. 22, 1936UNirEo raras PATENT OFFICE TRAIN BRAKING SYSTEM Application September24, 1935, Serial No. 41,838

12 Claims.

This invention relates to a brake equipment for use on multiple unitcars and railway trains and more particularly to such equipment adaptedfor use on high speed trains.

In certain types of high speed train braking equipments, a straight aircontrolled portion is provided for controlling service applications ofthe brakes, and an automatic controlled portion is also provided foreffecting service' applications in the case of failure of the straightair controlled portion, and for effecting emergency applications.

An automatic emergency application of the brakes will result in the caseof a broken train and may also be elected from any car of the4 train.

Uniform braking pressure is assured in the several brake cylinders inthe case of the straight air controlled application, since the severalbrake cylinders are all supplied with fluid under pressure in accordancewith the uid pressure developed in the common straight air pipe. In thecase of an automatic brake application, however, where upon a reductionin brake pipe pressure fluid under pressure is supplied to each brakecylinder from the associated auxiliary reservoir, there is a possibilitythat differences within the several brake cylinders may result, causedby leakage from the brake cylinder, variations in brake cylinder pistontravel and the like, and which will produce different braking forces atdifferent points in the train.

In accordance with my invention I provide a brake equipment comprising astraight air portion having fast application and release characteristicsand provided with electrically controlled magnet valve devices of acontrol valve assembly for controlling the application and release ofthe brakes, and an automatic control portion that is capable of eitherservice or emergency application. A retardation controller, in the formof an inertia responsive device, is provided for controlling the magnetvalve devices of the straight air portion of the equipment to limit thedegree of application of the brakes to prevent the rate of decelerationof the vehicle from exceeding a predetermined value. The automaticcontrol portion is not under control of the retardation controller.When, however, an automatic emergency brake application is made, atransfer switch is operated to effect operation of the straight airportion of the equipment if the straight air equipment is in serviceablecondition. The straight air portion of the equipment will overcome theautomatic portion and the automatic brake application will be convertedinto a straight air application of the brakes which is under the controlof the retardation controller. The setting of the retardation controlleris infiuenced by the brake pipe pressure such that the venting of brakepipe air will effect a change in the setting of the retardationcontroller to permit a higher rate of deceleration of the vehicle thanis effected during service application of the brakes.

It is an object of my invention to provide a fluid pressure brakeequipment that is quick acting both in applying and in releasing thebrakes.

It is another object of my invention to provide a brake equipment havinga straight air controlled portion that is subject to the control `of aretardation controller device, and having also an automatic controlledportion that is independent of the control of the retardation controllerdevice.

It is a further object of my invention to provide for converting .anautomatic controlled application of the brakes into a straight aircontrolled application of the brakes when the straight air portion ofthe equipment proves to be in operating condition.

Other objects and advantages of my invention will be apparent from thefollowing description of one embodiment thereof taken in connection withthe accompanying drawings in which,

Figs. l and 2 taken together comprise a diagrammatic view partly insection showing circuits and apparatus illustrating one preferredembodiment of the invention, and

Fig. 3 is a diagrammatic view of the brake valve.

Referring to the drawings, each car or train braking unit may beprovided with braking equipment including a brake cylinder l and acontrol valve assembly 2 that is controlled either electrically orpneumatically in accordance with the operation of a brake valve device3, which comprises an electric self-lapping portion for controlling theelectrical portion of the control valve assembly to effect the supply offluid under pressure from the supply reservoir 4 to the brake cylinderl, and from the brake cylinder I to the atmosphere, and which alsocomprises a pneumatic portion for controlling the pneumatic portion ofthe control valve assembly to effect the supply of fluid under pressurefrom the auxiliary reservoir 5 to the brake cylinder l to theatmosphere. A retardation controller device 6 is provided for limitingthe degree of application of the brakes when effected by electricalcontrol of the control valve assembly. A vent valve device 1 is providedfor elfecting a rapid venting of the brake pipe upon an initialreduction in brake pipe pressure at an emergency rate, such as mayresult from a broken brake pipe or by operation of the safety controlsystem upon pressure being released from the lever of the foot valvedevice 8. A transfer switch II is provided that is operated uponoperation of the vent valve device to effect a straight air applicationof the brakes.

The brake valve device 3 may comprise an electric self-lapping portionfor controlling normal service applications of the brakes and a rotaryvalve portion for controlling auxiliary service and regular emergencyapplications, and is provided with a casing I2 dening a chamber I3through one end of which an operating shaft I4 extends that is providedat its upper end with a brake valve handle I5.

A cam I5 for controlling the electric selflapping portion is carried bythe shaft I4.` The upper face of the cam engages the rounded end I1 of aoating operating lever vI8 that is urged downwardly against the face ofthe cam by a spring 2|, that lis positioned between the upper wall ofthe brake valve casing structure and the `end I1 of the lever I8. Theother end of the floating lever I8 is pivotally connected by a pin 22 toa guiding and actuating member 23 that is intertted within a bore 24 inthe brake valve casing. A contact carrying lever 25 is pivotallyconnected by a pin y26 to the guide member 23, and carried'movablecontact members 21 and 28 that are connected to a common conductor 3|and are adapted to engage, respectively, the xed contact members 32 and33 mounted on the casing structure, as shown. The contact carrying lever25 is urged upwardly by springs 34 and 35, the lower ends of which areinserted in recesses in the casing structure and the upper ends of whichengage the left hand end and the right hand end, respectively, of thecontact carrying lever 25 as viewed in the drawings, and vpressupwardlyuntil the left hand end thereof engages a stop 36 and thecontact member 28 on the right hand end engages the contact member 33,unless and until the contact carrying lever 25 is forced downwardly vbyVthe floating lever I8 and the guide member 23.

The floating lever I8 is pivoted at aY point intermediate its end on apin 31 that is supported'in a stem 38 that extends upwardly from aselflapping piston 4I contained in the piston chamber 42. A spring 43 ispositioned about the stem 38. having its lower end in engagement with aself-lapping piston 4I and its upper endin engagement with a nut'44urges the piston 4I Vclownwardly to its illustrated position. Therelative forces exerted by the spring 43 and the springs 34' and 35faresuch that when the left hand end I1 of the floating lever I8 is vin itslower or illustrated position, the springs 34 and 35 exert a suicientupward force on the contact carrying lever 25 and the guide member 23 toeifect separation of the contact members 21 and 32 and engagement of thecontact members 28 and 33.

The rotary valve 45,v contained within a valve chamber `46, is providedwith a port 41 that is adapted to register with a passage 48 leadingthrough the pipe 48 and the vent valve device 1 tothe Abrake pipeVV 5I,so that fluid at a reduced pressure, as supplied through the feed valvedevice 52 from the main reservoir 53 and the main reservoir pipe-andpassage54 is -supplied through the port. 41 to the 'pipe 48 'and thebrake pipe 5I.

In pneumatic service position the brake pipe 5I is connected to theatmosphere exhaust port 55 through a cavity 56, see Fig. 3, andin'pneumatic emergency position the brake pipe 53 is connected to theexhaust port 55 through a cavity 51.

The straight air pipe 58 communicates with the piston chamber 42containing the self-lapping piston 4I, and also with the magnet valveapplication valve chamber m3 and with one side of the check valve deviceof the control valve assembly for a purpose to be later explained.

lThe retardation controller 6 comprises an inertia device such as apendulum 6I, contained within a casing 62 and pivotally supportedthereto by a pivot pin 63. The pendulum 6I is adapted, upon apredetermined movement towards the left, to move the contact member 64,carried at the lower end thereof, out of engagement with fixed contactmembers 65 and 66 and upon a further predetermined movement toward theleft to bring the contact member 34 into engagement with` the contactmembers 61 and 68.

The "pendulum 6I is engaged byspring pressed plungers 1I and 12, thatrestrict its movement from a vertical position. The plunger1l isprovided with aicentral bore for accommodating a spring 14, one end ofVwhich is in engagement with the lower end of the bore, and the other endof which is in engagement with an adjusting member 15 carried by a guidemember 16 within a bore in the `casing portion 11 of the retardationcontroller structure, and'which is adapted to engage one end of a lever18 pivotally mounted on the casing structure by the pivot pin 8l. Theadjusting member 15 moves within a bore within a stop member 82 that isattached within the other end of a sleeve 83, the lower end of whichsurrounds and supports the plunger 1I. The plunger 1I is provided at itsouter end with an outwardly extending flange 84 that engages a shoulderon the sleeve 83 to limit` the movement of the plunger toward thependulum. The lower end of the sleeve 83 is provided with an outwardlyextending ange 85 that engages a portion ofthe controller casing tolimit its inward movement, and to accommodate a spring 86 that ispositioned about the sleeve. The lower end of the spring 86 engages theoutwardly extending flange 85 and the upperend is contained within aninwardly extending shoulder in a sleeve 81 attachedto the controllercasing.

A piston chamber is provided in the lower part Aof the controller casingthat is in constant communication with the brakek pipe 5I, and thatcontains a piston SI having a stem 92 provided vwith an opening 93surrounding the lever 18. A spring '54 is providedsurrounding the stemk92 betweenthe inner face of a piston 3|l and the outer wall of thecasing, the force of which opposes the force of the pressure within thepistonichamber,

Upon some predetermined rate of deceleration of the vehicle, assumingthe movement of the vehicle to be toward the left as viewed in Fig. 2,the'inertia of the pendulum 6! will be'suilicient to move it and theplunger 'SI toward the left against the bias Yof the .spring "le untilthe ange 84 Vengages the stop-82 and the switchco'ntactmember 54 ismoved out of engagement with-the fixed contact members`55 and '56. Theforce ofthe spring SS is suicient to maintain `the sleeve 83 in itsillustrated positionfin which'the sleeve flangef85 is maintained inengagement with A'the "controller casing. Upon apredetermined greaterrate of deceleration of thevehicle, the inertia of the pendulum 6I 'willforce the plunger `1I further toward the left causing the stop ,member82 'and the sleeve 83 to move against the bias of the spring 86 untilthe switch contact member 64 is brought into engagement with the switchcontact members 61 and 68 to complete a circuit between them. The partsassociated with the spring pressed plunger 12 are identical inconstruction and operation with those 'associated with the springpressed plunger 1| excepting thatthe adjusting member 'i5 isscrewthreadedly attached to the stop member 82 and is adjustable byscrew-threadedly varying the position` of the adjusting nut with respectto the stop member rather than by a lever corresponding to 18.

So long as normal brake pipe pressure is maintained within the pistonchamber 88 the piston 9| is forced against a shoulder on the casing, asillustrated,- and the lever 18 is in its extreme left hand position,thus effecting a predetermined force on the vouter end of the springmember 14 to effect a predetermined adjustment of the force required bythe pendulum 6| to move the contact member 64 out of engagement with thecontact members 65 and 66. Upon a predetermined reduction in brake pipepressure the spring 94 forces the piston 9| and the stem 92, operatingthe lever 18, toward the right to force the adjusting member 'i5 towardthe pendulum 6| and effect a compression of the spring 14 such as torequire a greater force oi inertia of the pendulum 5| to cause movementof the contact member 64 out of engagement with the contact members 65and 66, and a correspondingly greater force necessary to causeengagement of Y the contact member 64 with the contact members 61 and68.

The control valve assembly 2 comprises a pipe bracket section 85, amagnet valve section 96, a triple valve section 81, and a double checkvalve section 98. The magnet valve section 96 comprises an applicationmagnet valve device |8| and a release magnet valve device |62. Theapplication magnet valve device |64 comprises a casing containing anapplication valve chamber |63 that is in constant communication throughpassage and pipe 84 with the supply reservoir 4, and a chamber |65 thatis in constant communication with the straight air passage and pipe 58.Communication between these two chambers is controlled by an applicationvalve |66 operatively connected to a magnet |31 of the magnet valvedevice. A spring |68 is provided in the application valve chamber 83 toforce the application valve |86 toward its seat.

The release magnet valve device |82 comprises a casing containing arelease'valve chamber that is in constant Vcommunication with thestraight air passage and pipe 58, and a chamber ||2 that is in constantcommunication with the atmosphere through the exhaust port i3. A releasevalve lil is provided within the release valve chamber that isoperatively connected to the magnet ||5 in the upper portion of thecasing. A spring |6 is provided in the release Valve chamber to forcethe release valve I4 to its seat.

The triple valve section 91 comprises a casing having a piston chamber|2| that is in constant communication with brake passage and pipe 5|,and that contains a piston |22 provided with a stem |23 that operativelyengages a slide valve |24 and a graduating valve |25 contained within aslidevalve vchamber |26 Within the casing of the triple valve sectionthat is in constant communication, through passage and pipe |21, withthe 'auxiliary reservoir 5. A graduating stem |28 is provided above thepiston |22, and is forced to its ylovver illustrated position by aspring |3`|, the lower end of which terminates in the lowerend of a borewithin the graduating piston |28, and-the upper end of which terminatesin a bore in acap nut |32.' Double check valves |33 and |34 are providedin the triple valve section for controlling the charging of the supplyreservoir 4 from the piston chamber |2| through` the passage and pipe|04.

The double check valve section 98 comprises a casing having a chamber|35 containing apiston valveV |36 for controlling communication tofthebrake cylinder and which provides a chamber |31 to the left of the valve|36 and a chamber |36 to the right thereof, as viewed in Fig. 2.. Theleft hand chamber |31 is in constant communication with the straight airpassage and pipe 58. The right hand chamber |38 is in communication withthe atmosphere through passage |38, the' cavity |4| in the slide valve|24 of the triple valve device, and the passage and pipe |42 with thetriple valve piston and stem in their release position. A slide valve'|43 is operatively connected tothe stem of the piston valve |36 andcontains a groove |45 through which a safety valve device E44 isconnected to the passage |38 when the piston valve |36 and the slidevalve |43 are in their illustrated positions the valve |36 seatingagainst its right hand face. Passage and pipe |46 connects either thechamber |31 or the chamber |39 of the double check valve device with thebrake cylinder depending upon the position of the piston valve |36. Acavity |41 in the piston valve |36 connects the left hand branch of thepassage |46 to the passage |38 when the piston valve |36 is seatedagainst its left hand face.

The vent valve device 1 comprises an emergency valve portion |5| and asafety control vent valve portion |52. The emergency valve portion 5|comprises acasing dening a slide valve chamber |52 containing a mainslide valve |53 and a graduating valve |54, and defining a pistonchamber |55 containing a piston |56 having a stem |51 that extends intothe chamber |52 and is recessed to receive the graduating valve |54 andis operatively connected to the main slide valve 53.

The main slide valve |53 is held upon its seat by a loading mechanismcomprising a flexible diaphragm |58 mounted in the casing of the valvedevice, and adapted to be urged into engagement with a rocking stem |6|bearing upon the main slide valve |53. A spring |62 exerts a constantdownward pressure upon the flexible diaphragm |53. The chamber above thediaphragm |58 is in constant communication through a passage |53 withthe feed valve pipe 54, so that iluid under pressure corresponding tofeed valve pipe pressure is at all times supplied to the chamber abovethe flexible diaphragm |58.

The slide valve chamber |52 is in communication, by way of a passage|64, with a quick action chamber |65 formed in the casing of theemergency valve portion of the vent valve device. The emergency pistonchamber |55 is in communication with brake pipe passage and pipe 5|.

Formed in the lower part of the casing of the emergency valve portion isa vent valve chamber |66 that is in constant communication with brakepipe passage and pipe 5| and which contains a vent valve |61 that isnormally forced to its rib seat |68 by a spring |66. The vent valve |61controls the ow of fluid under pressure from the brake pipe 5| to theatmosphere.

To provide means for operating the vent valve '|51 from its seat aventvalve piston chamber |1| is provided in the casing, containing apiston |12 havinga stem |13 operatively connectngthe piston tothe ventvalve |81. `Whenfluid'under preslsureissupplied to the pistoncharnber|l1|pthe vent valve pistoni |12v and the vent valve |51are Aforced'downwardly, unseating the valve and releasingfiuid under pressure from'thev brake pipe 5| `to theatmosphere. When the flow of fluid underpressure tothe piston,A chamber |1| takes place at a slow rate it mayleak around the piston by way of a groove |14 and thus vflow to theatm'osphere without actuating the piston |12 to unseat the vent Valve. YThe main slide valve |53 is adapted to control the ports and passagesfor a purpose and in a manner which will be more fully described inthe-description of operation of the equipment.

v The safety control ventvalve portion |52 comprises a casinghaving apiston chamber |15 containing a piston |16 provided with a stem |11 thatextendsinto a slide-valve chamber |18, also provided in the casing, andwhich contains a slide valve |19 that is operatively engaged by thepiston stem |11.

A spring |8| is provided in the piston chamber |15 for urging the piston|18 and the slide Valve |19 towards the left, or to their illustratedposition. The slide valve chamber |18 is in constant communication withthe feed valve pipe 54 through passage |53. The piston chamber |15 isalsofnormally lincommunication withthe feed valvepipe 54 throughpassageand pipe |82, and the foot valve device 8, as will presentlyappear. A leakage groove |83 is provided for equalizing theA pressureson either vside of the piston |15 when in this position to preventundesired operation. The safetyV control vent valve portion |52 operatesto eifect an emergency application of the brakes in response tooperation of safety control devices, of which the foot valve device 8 isillustrative.

The foot valve device 8 comprises a casing vin which is provided a valvechamber |83, that is in constant communication with the feed valve pipe54, and contains a valve |84 that is urged towards its seat by a spring|85. The valve |84 is adapted to control communication between thechamber .|83 .and anintermediate chamber |86 of thefoot valve device,which is in constant communication throughthe safety control pipe andpassage |82 zo v with the piston chamber |55 of the safety control ventvalve portion. Communication between this intermediate chamber v| and anexhaust chainber |81, thatis in constant communication with theatmosphere through an exhaust port |88, is controlled by a diaphragmvalve |9| that is adapted Vto be forcedto its seat |92 by an operatingstem |93 upon the downward movement of a foot valve lever |94, that ispivotally supported on a pin |95. A spring|95 is provided for forcingthe lever |94 upwardly when pressure thereon vis released. The valve |84is provided with a-stem |91 for engaging the diaphragm valve -|9| toforce the vvalve |9| fro-m its seat when the Valve |84 is forced to itsseat.

The transfer switch comprises a casing having a piston chamberl that isnormally in communication 1 with the atmosphere through pipe andpassageii, the cavity 203 of lthe main slide valve |53 4of the emergencyvalve portion, passage 284, and exhaust port 205. The Apiston chamber28| contains a piston 255 having va stem 201 extending upwardly throughthe topof uthe casingand carrying ya switch contact member 208 havingtwo ,operative circuit closingpositions. A spring 209 is provided withinthe casing about the stem 201 for forcing lthe piston 206 and the switchcontact member 208 downwardly.

The system is charged as follows. VFluid under pressure'ows from themain reservoir 53 through `the feed valve device 52 to the feed Valvepipe 54 .at feed valve pressure and from the pipe, 54,

through passage |63V to the vslide valve chamber |18 ofthe safetycontrol portion |52 of the-vent valve device Land-also from the passage|53 toV the loading chamber above the diaphragm y| 58 of the emergencyvalve portion. In order to complete the charging of the system itisnecessary to apply pressure tothe lever |94 of the foot Valve device 8,holding the lever in its lower or illustrated position, andV effectingcommunication from the feed valve pipe 54 through the valve chamber|83,- past the vunseated valve y|84 to the middle chamber |86, andthrough pipe and passage |82 to the piston chamber |15 of the safetycontrol-vent valve portion, thus maintaining the piston |1|and the slidevalve |19 in their illustrated positions to permit the charging of thebrake pipe in `the manner to be presentlyde-V scribed.

Fluid under pressure also flows from the feed .the feedV groove 2| tocharge the Vslide valve chamber` |52, and from the slide Valve chamberthrough the port :|64, to charge the quickaction chamber |55. Y Y

One branch of the brake pipe 5| terminates in the seat of the rotaryvalve of the brake valve device 3, Vat which point communication isclosed bythe valve 45 when in its release and charging position. Anotherbranch of the brake pipe'5l Ais connected to the piston chamber 88 ofthe retardation controller device which, when charged, forces the piston9| toward its -left face against the bias of the spring .94 to set theretardation controller Yto effect a service rate of retardation of thevehicle.

The. brake pipe 5| extends rearwardlythrough the train having branchesat .each controlv valve assembly 2 controlling one of the braking units,of the train, oneonly of which is illustrated-in Fig.,2. Throughsuchbranch pipe the piston vchamber |2| of the triplevalve portionof the.control valve assembly is charged-,from which,

fluid under pressure flowsk past the piston |22 through the feed grooveA2,20 toV the slide valve chamber v|28, and through passage and pipe |21to the auxiliary reservoir 5 to charge the slide Valve chamber and theauxiliary reservoir. Fluid under pressure also flows from piston chamber|2| past the double check valves |33 and |34 to the passage-and pipe |04to charge the supply reservoir 4, and the application valve chamber |03of themagnet, valve portion. The check valves 33 and |34 prevent theflow of uid under pressure from the supply reservoir 4 to the pistonchamber |2| `upon a reduction in brake pipe pressure, thus retainingsupply reservoir pressure for ,service application of the brakes.

If the operator wishes to make a service applivalve :device 3 is movedfrom its-release position cation of the brakesfthehandle |5 of the brakel to a position within its electric application zone, depending upon thedesired degree of application of the brakes. As the brake valve handleI5 is thus moved the cam I3 is rotated about its axis thus raising theend I1 of the oating lever I8 which pivots about the pin 31 forcing theactuating member 23 downwardly. Upon downward movement of the actuatingmember 23 and the pivot pin 25, the contact carrying arm 25 pivots aboutthe stop 35, the left hand end of the lever being held in engagementwith the stop 36 by the spring 3ft until the right hand end of the leverhas moved downwardly suflicient to cause separation of the contactmembers 28 and 33 against the bias of the spring 35, it being understoodthat the spring 34 exerts a greater force than does the spring 35, thusmaintaining the left hand end of the contact carrying lever 25 inengagement with the stop 35. The downward movement of the right hand endof the contact carrying lever 25 continues until it is brought intoengagement with a stop 2 I4, which serves as a fulcrum for furthermovement of the contact carrying lever 25 upon further downward movementof the operating member 23, and causes the left hand end of the lever 25to move downwardly until the contact member 21 engages the contactmember 32.

When the brake valve device is in its illustrated, or release positi-ona circuit is completed from the battery 2I5 through conductor 3|,contact members 28 and 33 oi the brake valve device, conductor 2I1, theswitch contact member 238 of the transier switch in its lower position,conductor 2I8, and the winding of the magnet H5 of the release magnetvalve device |02, to ground at 2 I9, and to the grounded terminal 22| ofthe battery 2I5. The magnet H5, thus energized, forces the release valveH4 downwardly from its seat against the bias of the spring H6, thuselecting communication from the straight air pipe 53 to the atmospherethrough the chamber I l2 Vand exhaust port H3.

Upon separation of the contact members 28 and 33 of the brake valvedevice, as above described, when the brake valve handle I5 is moved fromits releaseV position this circuit is interrupted, thus deenergizing themagnet H5 of the' the further movement of the'4 lever 25 down` wardly tocause engagement of the contact members 21 and 32 a circuit is completedfrom the positive terminal of the battery 2 I 5, through conductor 3|,the contact members 32 and 21, conductor 222, the contact members 64, 65and 56 of the retardation controller device 5, conductor 223, thewinding of the magnet |01 of the application magnet valve device IGI, toground at IS, and to the grounded terminal 22| of the battery 2I5. Theenergization of this circuit forces the application valve 06 downwardlyfrom its seat against the bias of the spring |08 thus effectingcommunication from the supply reservoir 4 to the straight air pipe 58,from which uid under pressure flows to the chamber |31 to the left ofthe piston valve |33 of the double check valve section 58 of the controlvalve assembly, forcing the piston valve |35 toward the right tc opencommunication through the leftA hand branch of the passage to the brakecylinder pipe |45, to supply fluid under pressure to the brake cylinderI.

As fluid under pressure is thus supplied to the brake cylinder, duidalso flows from the straight air pipe 58 to the self-lapping pistonchamber 42 of the brake valve device 3, causing the pressure within thechamber 42 to correspond to that supplied to the bra-ke cylinder I. Aspressure within the piston chamber 42 increases the upward force on theself-lapping piston 4I, this force acts against the downward force ofthe spring 43 to move the piston 4I and its stem 33 upwardly, causingthe floating lever I8 to iulcrum about its rounded end I1 to move theactuating member 23 and the pivot pin 26 upwardly. As the pivot pin 26moves upwardly the spring 34 causes the contact carrying lever 25 tofulcrum about its right end, on the stop 2I4, thus causing the contactmembers 21 and 32 to separate. Upon separation of the contact members 21and 32, the circuit through these contact members and through thewinding of the magnet |01 of the application magnet valve device IOI isinterrupted and the spring I 08 urges the application valve |05 to itsseat, cutting off further flow of fluid to the brake cylinder and to theself-lapping chamber 42.

The greater the movement of the handle I5 of the brake valve device fromits release position the greater will be the upward movement of therounded end |1 of the floating lever I8 on the cam I6 and consequentlythe greater will be the required upward movement of the pivot pin 31carried by the stem 38, and of the piston 4I to effect rotation of thefloating lever I8 about the end I1 to a self-lapping position.Consequently, the greater will be the pressure within the self-lappingchamber 4I necessary to oppose the downward force of the spring 43 toeffect a self-lapping position of the contact carrying lever 25. Itfollows that the brake valve device 3 operates as a self-lapping brakevalve to elect a supply of fluid under pressure to the brake cylinder ata value dependent upon the amount of movement of the handle I5 withinits electric application zone.

In a similar manner, movement of the brake valve handle I5 from aposition within its electric application zone toward its releaseposition effects a corresponding movement of the cam I6, and a loweringof the fulcrum point formed by engagement of the cam with the groundedend I1 of the oating lever I8. This causes the lever I8 to pivot aboutthe pin 31 to move its right hand end, together with the contactcarrying lever 25, upwardly to cause engagement of the contact members28 and 33 to effect the energization of the winding of the magnet I I5of the release magnet valve device |02, which forces the release valveH4 downwardly from its seat against the force of the spring H6 andpermits the ow of fluid under pressure from the brake cylinder I, thestraight air pipe 58, and the selflapping piston chamber 42, to theatmosphere through exhaust port H3. Should the operator move the brakevalve handle I5 only part of the way from its previous position towardrelease position, to partially release the brakes,l

the rounded end I1 of the floating lever I8, upon its downward movement,will engage the cam' contact members 21 and 32 are in engagement,eiecting the supply of fluid under pressure through the applicationmagnet valve device IUI tothe brake cylinder I and the piston chamber 42of the brake valve device 3, and assuming that the vehicle is moving insuch direction as to carry the pendulum 6I of the retardation controldevice 6 towards the left as viewed in Fig. 2, and if, While the brakesare so applied, the rate of retardation ofthe vehicle becomes suicientto cause the pendulum 6I to swing toward the left to actuate thespringpressed plunger 1I against the stop member 82, the Yswitch contactmember 64 will interruptthe circuit through the contact members 65 and66. The circuit through the winding of the magnet |61 of the applicationmagnet valve device I IlI,'thus interrupted, permits the spring |08 toforce the application valve |06 to its seat :and close communicationfrom the supply reservoir 4 to the brake cylinder I and to the straightair pipe 53, thus preventing a further degree of application of thebrakes. In this position of the retardation controllerpendulum, theapplication and release magnet valves |06 and I I4, respectively, willbe in lap position.

If the rate of retardation of the vehicle becomes suicient to cause thependulum 6I to swing further-toward the left, so as to move the springpressed plunger 1| and the stop member 82 carrying the sleeve `83against the pressure of the spring 86 the switch contact member 64 willbe brought into. engagement with its switch contact members 61 and 68,thus closing the above traced circuit-through the winding of the magnetI|5 of therelease magnet valve device v|Il2,to force the release valveII4 downwardly against the force of the spring H6, and eiect the releaseof iluid under pressure from the brake cylinder I and the straight airpipe 58 in the manner above described, until the rate of retardation ofthe vehicle has become sufcient to cause the pendulum 6I to swing towardthe right a suicient amount to permit theswitch contact member 64 tomove out of engagement with the contact members 61 and 68 to interruptthe circuit through the windingv of the magnet I I 5, and permit thespring I|6`to force the release valve l||4 to its seat.

If, for any reason, the straight air portion of the brake equipmentshould be rendered inoperative, such as by interruption of the circuitsthrough. the wires leading from the brake valve device to theapplication magnet valve device and the release magnet valve device, theoperator may effect an automatic application of the brakes by movementof the brake valve handle beyond its-,electric application Zone to itsautomatic service application position as dened by the notch plate, 224,and as shown diagrammatically in Fig. 3. It will be apparent, byreference to Fig.y 3, that whenl the rotary valve 45 is lin a releaseZone, and the triple valve which controls the automatic application ofthe brakes is in its release position for any position of the brakevalve lever I5 within the electric application zone, and in automaticlap position. The automatic service application position and theautomatic emergency application position of the lever I 5 and of therotary valve 45 are beyond the'electric application Zone.

If rthe operator desires to elTect a pneumatic serviceA application ofthebrakes he moves the brake valve` handle I5 lto its automatic serviceapplication position, inwhich position fluid under pressure is ventedfromthe vbrake pipe 5| at a. restrictedVA rate Ithrough the vcavity 56in the rotary valve 45, and the exhausttportr55. The reduction in brakepipe pressure thus effected causes a corresponding reduction in pressurein the piston chamber I 2| of the triple valve portion of the controlvalve assembly, and within the emergency piston chamber |55 of the ventvalve device. The reduction in pressure within the piston chamber |2| ofthe triple valve device causes the piston |22 and the piston stem |24to' bemoved upwardly, first moving the graduating valve |25 to uncoverthe port 225 in the main slide valve |24, and then, upon engagement of ashoulder 226 on the lower end of the stem |23 with the end of the mainslide valve, the slide valve |24 is moved until the port 225 registersVwith the passage |38, thus closing communication from passage |38 tothe exhaustpassage I 42 through the cavity I4I in the slide valve, andeiecting communication from the auxiliary reservoir 5 and the slidevalve chamber |26 to the brake cylinder I through the port 225 in themain slide valve, passage |38, to the chamber |39 at the right hand endof the double check valve |36 causing pressure to build up to force thevalve to seat on its left face, and to open communicatior'i from thechamber |31 at the right of the piston valve |36 through the rightbranch passage |46, and pipe |46 to brake cylinder I. The supply offluid under pressure from the auxiliary reservoir 5 to the brakecylinder I, through the passages just described, continues until thepressure within the slide valve chamber |26 on the under side of thetriple valve piston |23 decreases to a value corresponding to, orslightly less than, the pressure on the upper side of the piston |22when the piston and stem |23 are moved downwardly until the graduatingvalve |25 laps the port 225 and closes communication through the passage|38 to the brake cylinder I, thus maintaining brake cylinder pressure ata value corresponding to the amount of reduction in brake pipe pres- Ysure.Y

The reduction in pressure in the emergency piston chamber |55 causes theemergency piston |56` and its stem |51 to move toward the rightslightly, or until the port 221 in the graduating valve |54 is broughtinto registration with the port 228 in the main slide valve |53,registering with the exhaust port 265. At the same time feedV groove 2I0is closed by piston |56. Fluid under pressure is then'vented from thequick action chamber |65 through port |64, and fromrthe slide valvechamber |52, tothe atmosphere through the ports 221, 228, and theexhaust port 205. 'Ihe size of the port 221 is such that the rate ofreduction in pressure on the left hand side of the piston |56corresponds substantially to a servi'ce rate of reduction in pressure inthe piston chamber |55, so that, in automatic service application, thepiston |55` and stem |51, do not move to the right suiciently to effectthe supply of uid under pressure to the piston chamber I1I of the ventvalve device.

`If the operator wishes to make an emergency application of the brakesthe handle I5 is moved to its automatic emergency position thus rotatingthe valve 45 to such position th-at the cavity i 51 therein effectscommunication from the brake pipe 5I to the atmosphere through theexhaust port 55 to effect an emergency rate of reduction in brake pipepressure, When the pressure in the 221 in the graduating valve |54 sothat the pressure in the slide valve chamber I 52 forces the piston |56and the graduating valve |54 toward the right until the passage 228 islapped and the end of the port 229 through the main slide valve |53 isuncovered. This effects communication from the main slide valve chamber|52 to the vent valve piston ch-amber |1| through port 229 and passage232 to effect the supply of fluid under pressure from the quick actionchamber |65 and the slide valve chamber |52 to the piston chamber |1| toforce the piston |12 and the vent valve |61 downwardly from its seat |68to effect a rapid reduction in brake pipe pressure past the unseatedvvent valve.

This rapid reduction in brake pipe pressure and in the pressure in thepiston chamber |55 causes the piston |56 and its stem |51 to movefurther toward the right, the shoulder |3| on the end of the piston stemengaging and moving the main slide valve |53 to uncover the end of thepassage 232 to permit the flow of fluid under pressure past the end ofthe slide valve to the.

piston chamber |1|. The movement of the slide valve |53 toward theright, as just described, brings the cavity 203 therein to a position toeffect communication between the feed valve pipe 54 and the transferswitch passage and pipe 202 through a passage 234 past the unseatedcheck valve 235, thus supplying iiuid under pressure to the pistonchamber 20| of the transfer switch device to force the piston 206 andthe contact member 208 upwardly against the bias of the spring 209 tointerrupt communication between the conductors 2I1 and 2 |8 and effectcommunication between the positive terminal of the battery 2|5 and theconductor 222. The check valve 235 is weighted by a spring 236 to effecta differential in pressure between the feed valve 54 and the transferswitch device 202.

Movement of the contact member 208 of the transfer switch device fromits illustrated position to its upper contact making position interruptsthe circuit through the winding of the magnet ||5 of the release magnetvalve device |02, that is normally completed from conductor 3 I throughcontact members 28 and 33 of the brake valve device, and conductors 2|1and 2|8. Upon deenergization of the magnet I5, the spring |I6 forces therelease valve |4 to its seat as above described, thus closingcommunication between the brake cylinder and the atmosphere through theexhaust port ||3. The contact member 208 of the transfer switch deviceII, in its upper position, completes a circuit from the positiveterminal of the battery 2I5, through conductor 222, the contact members65, 64 and 66 of the retardation controller device 6, the conductor 223through the winding of the magnet |01 of the application magnet valvedevice |0| to ground at 2| 9, and to the grounded terminal 22| of thebattery 2I5, The energization of the winding of the magnet |01 forcesthe application valve |96 downwardly against the bias of the spring |68thus effecting the supply of fluid under pressure from the supplyreservoir to the brake cylinder I as previously described.'

This operation of the transfer switch l causes the emergency applicationof the brakes, initiated by an emergency rate of reduction in brake pipepressure, to be transferred to an electric application of the brakesthrough the circuits controlled by the retardation controller 6, so thatthe rate of retardation of the vehicle may be regulated. The reductionin brake pipe pressure may be effected by any cause, such as byoperation of a conductors valve, or rupture of the brake pipe, while thehandle I5 of the brake valve device remains in release position.

Upon a reduction in brake pipe pressure, the pressure within the pistonchamber 88 of the retardation controller device 6 is correspondinglyreduced, thus permitting the piston 9| and the stem 92 thereof to bemoved toward the right by the force of the spring 94 against the stop|40 thus moving the upper end of the lever 18 and the adjusting member15 toward the right to increase the pressure on the spring 14 to changethe setting of the retardation controller, so that a greater rate ofretardation of the vehicle and a corresponding greater force of thependulum 6| against the spring pressed plunger 1| is required to movethe contact member 64 out of engagement with the contact members 65 and66, to interrupt the circuit through the winding of the application 2magnet valve device I6 I ,and a corresponding greater force of inertiaof the pendulum 6| is required to move the plunger 1| to a position tocause engagement of the contact member 64 with the contact members 61and 68 to effect the operation of the release magnet valve device |02 torelease fiuid under pressure from the brake cylinder to limit the rateof retardation of the vehicle. The vehicle will therefore be brought torest with a greater rate of retardation than is effective when serviceapplication of the brakes is made.

Upon reduction in brake pipe pressure at an emergency rate, the pressurein the piston chamber |2I of the triple valve section of the controlvalve assembly 2 is correspondingly reduced, thus causing the piston |22and the piston stem |23 to be moved upwardly with such force against agraduated stem |28 as to cause a spring |3| to be compressed, and lowerend of the slide valve |23 to be moved to uncover the end of thepa'ssage |38 to supply uid under pressure from the auxiliaryreservoirthrough the slide valve chamber |26 and passage |38 to thechamber |39 at the right of the piston valve |36 of the double checkvalve device 98. A choke 24| is provided in the passage |38 so that thepressure within the chamber |39 builds up at a slower rate than pressurewithin the chamber |31 provided the magnet valve devices 0| and |02 haveoperated to effect the supply of fluid under pressure from the supplyreservoir to the brake cylinders through the chamber |31.

Should the magnet valve devices not operate properly, and should thepressure within the chamber |31, therefore, fail to build up, pressurewithin the chamber |39 will force the piston valve |36 toward the leftto seat on its left face against the end of the chamber |31, and effectcommunication from the chamber |39 through the right hand branch of thepassage |46, and brake'cylinder pipe |46, to the brake cylinder I, andat the same time, bring the right hand end of the cavity |41 in thepiston Valve |35 into registration with the end of the passage |38 inthe Valve seat, and the left hand end of the groove |41 intoregistration with the left hand branch of the passage |46, terminatingin the valve seat. to effect communication from the passage |38 throughthe groove |41 in the piston valve |35. and through passage and pipe |46to the brake cylinder Should the operator release pressure on the footlever |94 of the foot valve device 8, this lever will be forced upwardlyby the spring |96, and the spring will force the valve |84 to its seat,

closing communication from the feed valve pipe 54 through the foot valvedevice to the safety control pipe |82, the valve stem |91 forcing the`diaphragm valve ISI and the stem |93 toward the right, thus raising thediaphragm valve from its rib seat |92 to effect communication from thesafety control pipe |82 past the unseated diaphragm valve I9I, throughchamber |81, and exhaust port |88 to the atmosphere, to vent iiuid underpressure from the piston chamber |15 of the'safety control vent valveportion. The greater force on the left hand side of the piston |16therefore forces the pistonv |16 and the piston stem |15 toward theright against the bias of the spring IBI, thus moving the slide valve|19 to lap the end of the passage 43, through which the brake pipe 5I ischarged, and to bring the groove 2II' in the slide valve |19 to aposition to effect communication between the passage 2|2 and the exhaustport 242, to vent fluid under pressure from the emergency piston chamber|55 and the brake pipe 5| at an emergency rate to effect an emergencyapplication of the brakes in the mannerabove described.

lIt will be appreciated that the operation of the transfer switch device|I and the mechanism controlled thereby has particular utility when anapplication of the brakes is effected by reduction in brake pipepressure by other means than the brake valve device I5, and causes asmooth reduction of the vehicle at a rate of deceleration that isgreater than the normal service rate of retardation as controlled by theretardation controller 6.

While I have illustrated and described one preferred embodiment of myinvention, it will be apparent to those skilled in the art that manymodications thereof may-.be made within the spirit of my invention and Ido not ywish to 'be limited otherwise than by the scope of the appendedclaims.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent, is:

1. In a brake equipment for vehicles, a brake cylinder, magnet valvemeans for controlling the supply of fluid under pressure to said brakecylinder, an automatic valve device for controlling the supply of fluidunder pressure to said brake cylinder, manually operable means forcontrolling the operation of said magnet valve means and of saidautomatic valve device, a retardation controller responsive to the rateof retardation of the vehicle for controlling the operation of said'magnet valve means to effect a desired rate of retardation of thevehicle and means responsive to a reduction in brake pipe pressure foreffecting the operation of said magnet valve means to apply the brakeindependently of the-operation of said manually operable means.

2. In a brake equipment for vehicles, a brake cylinder, magnet valvemeans for controlling the supply of fluid under pressure to said brakecylinder, an automatic valve device for controlling f the supply offluid under pressure to said brake cylinder, manually operable means forcontrolling the operation of said magnet valve means and of saidautomatic valve device, a retardation controller device responsive tothe rate of retardation of the vehicle for controlling the operation ofsaid magnet valve means to effect a desired rate of retardation of thevehicle, means responsive to a reduction in brake pipe pressure'forVeffecting the operation orf said magnet valve means to apply the brakesindependently of thev operation of said manually operable means, andmeans responsive to a reduction in brake pipe pressure for effecting achange in the setting ofl said retardation controller to eifect agreater rate of retardation of the vehicle.

3. In a brake equipment for vehicles, a brake cylinder, electricallyoperated means for controlling the supply of uid under pressure to thebrake cylinder to effect a service application of the brakes, anautomatic valve device for effecting an automatic application of thebrakes, an inertia controller device for controlling'the electricallyoperated means for regulating the rate of retardation of the vehiclewhen electrically applied, and means operative upon an emergencyautomatic application of the brakes for effecting control of the brakesby said retardation controller device.

4. In a brake equipment for vehicles, a brake cylinder, electricallyoperated means for controlling the supply of iiuid under pressure to thebrake cylinder to effect a service application of the brakes, anautomatic valve device for eiecting an automatic application of thebrakes, an inertia controlled device for controlling the electricallyoperated means for regulating the rate 0f retardation of the vehiclewhen electrically applied, means operative upon an emergency auto'-matic application of the brakes for effecting control of the brakes bysaid retardation controller device, and means responsive to an emergencyapplication of the brakes for changing the setting of the retardationcontroller device to effect a rate of retardation of the vehiclegreater'than that effected during service application of the brakes.

5. In a iluid pressure brake for vehicles, a bra-ke cylinder,electrically operated means for controlling the supply of uid underpressure to the brake cylinder, a brake pipe and triple valve meansresponsive to a reduction in brake pipe pressure for controlling thesupply of fluid under pressure to said brake cylinder, a retardationcontroller for controlling said electrically operated means to controlthe rate of retardation of the vehicle, and means responsive to areduction in brake pipe pressure at an emergency rate for transferringthe control of the brakes to said electrically operated means.

6. In a fluid pressure brake for vehicles, a brake cylinder,electrically operated means for controlling the supply of fluid underpressure to the brake cylinder, a brake pipe, automatic valve meansresponsive to a reduction in brake pipe pressure for controlling thesupply of fluid under pressure to said. brake cylinder, a retardationcontroller for controlling said electrically operated means to controlthe rate of retardation of the vehicle, means responsive to a reductionin the brake pipe pressure at an emergency rate for transferring thecontrol of the brakes to said electrically operated means, and meansresponsive to a reduction in brake pipe pressure for changing thesetting of said retardation controller to eifect a greater rate ofretardation of the vehicle when the brakes are applied through operationof the automatic valve means than when applied electrically.

7. In a fluid pressure brake for vehicles, a brake cylinder,electrically operated means fer controlling the supply of fluid underpressure to the brake cylinder, a brake pipe, automatic valve meansresponsive to a reduction in brake pipe pressure for controlling thesupply of fluid under pressure to said brake cylinder, a brake valvedevice having an electrical self-lapping portion for controlling saidelectrically operated means and a rotary portion for controlling saidbrake pipe pressure, a retardation controller for controlling saidelectrically operated means upon electrical application of the brakes tocontrol the rate of retardation of the vehicle, a pressure operatedtransfer switch, and a vent valve device having an emergency valveportion operated upon a reduction in brake pipe pressure at an emergencyrate for effecting the supply of fluid under pressure to said transferswitch for eifecting an application of the brakes through saidelectrically operated means.

8. In a fluid pressure brake for vehicles, a brake cylinder, a controlvalve device having a magnet valve portion and a triple valve portionoperative for controlling the supply of fluid under pressure to, and therelease of uid under pressure from, said brake cylinder, a manuallyoperable means for operating the magnet valve portion and the triplevalve portion of said control valve device to effect the application ofthe brakes, and means responsive to emergency application of the brakesthrough operation of said triple valve portion for transferring thecontrol of the application of the brakes to said electrically operatedmeans.

9. In a fluid pressure brake for vehicles, a brake cylinder, a controlvalve device having a magnet valve portion and a triple valve portion,each for controlling the supply of uid under pressure to, and therelease of fluid under pressure from, said brake cylinder to apply thebrakes, a brake pipe, a manually operable means for effecting operationof the magnet valve portion, and of the triple Valve portion, of saidcontrol valve device to effect the application of the brakes, aretardation controller for controlling said magnet valve portion tolimit the rate of retardation of the vehicle to a desired Value, atransfer switch, a vent valve device having an emergency portion and asafety control portion, said emergency portion being responsiveA to areduction in brake pipe pressure at an emergency rate to effectoperation of said transfer switch to effect control of the brakes bysaid magnet valve portion, and safety means effecting operation of thesafety control portion to cause operation of the emergency portion toeffect an automatic application of the brakes.

10. In a uid pressure brake for vehicles, a brake cylinder, a controlvalve device having a magnet valve portion and a triple valve portion,

' each for controlling the supplyof fluid under pressure to, and therelease of iiuid under pressure from, said brake cylinder to apply thebrakes, a brake pipe, a manually operable means for electing operationof said magnet valve portion and of said triple valve portion of saidcontrol valve device to effect the application of the brakes, aretardation controller for controlling said magnet valve portion tolimit the rate of retardation of the vehicle to a desired value, atransfer switch, a vent valve device having an emergency portion and asafety control portion, said emergency portion being responsive to areduction in brake pipe pressure at an emergency rate to effectoperation of said transfer switch to effect control of the brakes bysaid magnet valve portion, safety means for effecting operation of thesafety control portion to cause operation of the emergency portion toeffect an automatic application of the brakes, and means responsive to areduction in brake pipe pressure for changing the setting of theretardation controller to effect an increased rate of retardation of thevehicle.

11. In a fluid pressure brake for vehicles, a brake cylinder, a controlvalve device having a magnet valve portion and a triple valve portionindependently operative for controlling the supply of fluid underpressure to, and the release of fluid under pressure from, said brakecylinder to control the application and release of the brakes, a brakepipe, a manually operable means for effecting the operation of themagnet valve portion of said control valve device to effect theapplication of the brakes and for controlling brake pipe pressure tocontrol the operation of said triple valve portion to eiect theapplication and release of the brakes, a retardation controller, forcontrolling said magnet valve portion to limit the rate of retardationof the vehicle to a desired value, a transfer switch, a vent valvedevice having an emergency portion, said emergency portion beingresponsive to a reduction in brake pipe pressure at an emergency rate toeffect the operation of said transfer switch to effect application andcontrol of the brakes through said magnet valve portion, and meansresponsive t a reduction in brake pipe pressure at an emergency rate forchanging the setting of the retardation controller to effect anincreased rate of retardation of the brakes.

12. In a vehicle brake system, in combination, braking means, straightair means for controlling the application of the brakes, continuouslyoperable automatic means for also controlling the application of thebrakes, means for controlling the degree of braking when the brakes areapplied by operation of said straight air means to limit the rate ofretardation of the vehicle to a predetermined value, and means operativeupon initiation of an application of the brakes by an emergencyapplication of said automatic means for effecting operation of saidstraight air means to effect an application of the brakes.

ELLIS E. HEWITT.

